Reproduction, sexual or asexual, is a means of survival of a particular species on the face of a planet. Angiosperms have many ways of reproducing themselves. It is of no surprise that the sex organs of a plant are in their flowers.

Introduction: Reproduction, sexual or asexual, is a means of survival of a particular species on the face of a planet. Angiosperms have many ways of reproducing themselves. It is of no surprise that the sex organs of a plant are in their flowers. Two major organs being: ovary and the anthers. Pollen is found primarily on the anthers, pollen [male gametophyte] is so widespread that we can find it almost everywhere, in the air we breathe, the soil we walk on etc. Physically it looks like a yellow, white or blue powdery substance. Pollen develops within the anther and after attaining maturity falls [by the means of air currents etc] onto the receptive stigma. The stored 'goodies' and RNA kick into action and start the most probably the most rapid growth of any plant cell. A tube known as the pollen tube grows from each pollen grain. This pollen tube grows toward the embryo sac. Eventually two sperm cells are deposited into the embryo sac where they fuse with the egg and form a zygote. Pollen germination is one of the most important processes insuring that a zygote is formed and the plant species continues and does not become extinct. Pollen germination is the stage when the pollen falls on the stigma and start growing the pollen tube. This process is vital since the ovary is located at the very bottom of the anther and is concealed from all 4 sides, making it almost impossible

  • Word count: 623
  • Level: University Degree
  • Subject: Biological Sciences
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Describe the major pathways and transformations involved in the atmospheric transport of Sulphur, produced as SO2 in combustion processes. Outline the major impacts of SO2 upon plants.

Describe the major pathways and transformations involved in the atmospheric transport of Sulphur, produced as SO2 in combustion processes. Outline the major impacts of SO2 upon plants. Sulphur is an essential nutrient for normal plant growth and development. The primary source of Sulphur is from the soil in the form of sulphate (SO42-), which is taken up by the roots and translocated to the leaves where most of it is reduced and assimilated into organic sulphur compounds. An important primary source of sulphur can be found in the atmosphere. 15 molecular species of Sulphur are found in the atmosphere, according to Berresheim et al (1995). Plants unable to acquire all the sulphur they need from the soil are able to use SO2 from the atmosphere or other volatile compounds such as H2S.When more SO2 is taken up from the atmosphere by plants then is needed, plants are adversely effected. SO2 is considered the most important phytotoxic molecule. Originally most sulphur combustion was carried out in widely scattered domestic appliances, increasingly with introduction of Pollution Abatement Legislation, energy generation became localised in large centralised facilities, such as those designed to produce electricity. These attempted to improve the local environment around them by building taller and taller stacks to disperse the gases higher into the atmosphere. Consequently, gases

  • Word count: 1530
  • Level: University Degree
  • Subject: Biological Sciences
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I plan to investigate how environmental conditions affect the transpiration of plants.

Aims I plan to investigate how environmental conditions affect the transpiration of plants. Background Information The Sun provides the energy to turn the water in the plants into a vapour causing it to evaporate into the leave's internal air spaces before diffusing out of the stomata into the air. This is known as transpiration. As the water evaporates out of the top of the plant it creates a suction on the column of water below it in the xylem. The upwards force on the column of water created by transpiration and the downwards force due to gravity created a tension in the column of water. As the upwards pull is greater than the downwards pull the column of water moves up the xylem. Cohesion tension theory tells us that it is the evaporation of water from the leaves which causes the upwards movement of water. The water molecules have a high cohesion as they are polar and so are electrically attracted to each other. They are held together by hydrogen bonds. The column of water does not tend to break as it has a very high tensile strength from the bonds. The water is able to evaporate out of the leaf as the leaf has a high water potential and the air has a low water potential so the water molecules pass down the concentration gradient from the spongy and palisade mesophyll cells into the leave's internal air spaces before diffusing out into the air. Transpiration is

  • Word count: 3150
  • Level: University Degree
  • Subject: Biological Sciences
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Is there evidence of plant succession with the old abandoned quarry at Maddocks Hill?

Is there evidence of plant succession with the old abandoned quarry at Maddocks Hill? Aims Throughout this study the following aims should be met: * What plant communities can be identified along the transect in Maddocks Hill Quarry * How does the occurrence of plant species vary along the transect? * Is plant diversity limited to entopic factors such as pH and soil moisture? * Does light and structure of plant life forms vary along the transect? * Can a definite plant succession be identified along a transect? Hypothesis "There will be taller plant life forms and different plant communities along a transect from the outer to inner parts of Maddocks Hill Quarry". Background Plant succession, a definition; "The natural and gradual replacement of one plant community by another." The process may begin on solid rock, soil or water, the end result being generally a forest tolerant (able to grow in the shade) trees. The stages in between may include moss, annual weeds, grasses, brush and intolerant trees (needing full sunlight) and mid-tolerant trees. The stages vary depending on the site and the process may take centuries to complete. The Ercall - 68 ha OS Map Ref. SJ 640 096 This is an attractive site adjacent to Telford and is part owned by the Shropshire Wildlife Trust and Telford and Wrekin Borough Council. Both the Ercall and The Wrekin are a Site of Special

  • Word count: 2547
  • Level: University Degree
  • Subject: Biological Sciences
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My summer garden

My summer garden As the weather warmed, so did my heart. I felt at peace and had a lack of responsibility that I took for granted. I wanted to get the most out of the all to short nirvana by spending my time in my garden, I liked my personal time there, to be alone with my thoughts and not having to care about anything, which I suppose may have seemed selfish. In the other seasons, my garden was either cold, wet or simply unappealing. But in the summer, it all came to life and a desire grew inside me to meet and greet the new energy flowing out of the plants and animals. As I strayed from my back door my soul would be overtaken by an assimilating force of warmth, sounds and sights all hitting me like a gust of wind. The corners of my mouth would turn up uncontrollably and I would forget everything. My mind would be intoxicated by the pure nature before me, and I had no desire to damage the boundless balance of the tiny forest. Before me would lie the carpet of grass, usually brown and withered, which would dampen my mood, but this morbid image would never overtake the entire stretch of grass. The sides of the garden would be lined with plants and flowers as high as me. There was not much variation of colour, but I was content with the lush greens of the large leaves. Overshadowing those were larger trees left to grow at their own will, they obscured the dull fence from

  • Word count: 1157
  • Level: University Degree
  • Subject: Biological Sciences
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The Effect of Stomata Opening on Plant Transpiration

The Effect of Covered Stomata on Plant Transpiration Nezar Alsaeedi IB Biology Higher Year 1 Mr. Connors May 7, 2005 Abstract: The purpose of this study is to find the effect of covered stomata on plant transpiration. The experiment was designed to examine the changes in texture of four Devil's Ivy leaves (Epipremnum aureus) affected by covered stomata and rate of transpiration. One leaf was completely coated with Vaseline gel. The second leaf was coated only on the front surface, while the third leaf was coated on the back surface with gel. The fourth leaf was left uncoated as a control variable. The four leaves were hung on a rope (50cm. long), 10cm. apart from each other. The leaves were exposed to the same amount of sunlight, temperature (32 degrees Celsius), and humidity (about 70 percent). The changes in the texture of the four leaves were observed over a one-week interval. The results showed slight loss of turgidity for the completely coated leaf, moderate flexibility and folding edges in partially covered leaves (front-surface and back-surface coated leaves), and tremendous flexibility, softness, and complete inward folding of the edges of the uncoated leaf. According to the results, it is concluded that the uncoated leaf with uncovered stomata had the higher rate of transpiration than the other completely and partially coated leaves. Introduction:

  • Word count: 1908
  • Level: University Degree
  • Subject: Biological Sciences
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To what extent does plasticity of dipterocarp seedlings affect growth and survival in the tropical rainforest environment?

To what extent does plasticity of dipterocarp seedlings affect growth and survival in the tropical rainforest environment? 050139246 The Journal of Ecology (September 2007) To what extent does plasticity of dipterocarp seedlings affect growth and survival in the tropical rainforest environment? Abstract This study focused on survival and growth of three dipterocarp seedlings in exposed areas compared with shaded areas of the tropical rainforest, in order to determine the role plasticity plays in this. All species of dipterocarp seedlings showed some degree of morphological plasticity in response to the different environments. Each of the three dipterocarp species showed equal plasticity in terms morphological traits when subjected to different light conditions. Chlorophyll content was found to be a genetic trait rather than a trait of plasticity. Herbivory was also found to be determined by species rather than environment. Damage by herbivores was found to play a larger role in plant growth and survival than anticipated, perhaps more so than plasticity. Further study is required to determine the extent herbivory affects the growth and survival of these seedlings. Introduction The importance of tropical rainforests and their role in supporting much of the world's biodiversity is widely acknowledged, yet there is worldwide concern over the consequences of human

  • Word count: 3398
  • Level: University Degree
  • Subject: Biological Sciences
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Surveying the Distribution and Abundance of Plants in Different Coppices

Surveying the Distribution and Abundance of Plants in Different Coppices Aim: To survey the distribution and abundance of plant species in old and new coppice woodland and determine the factors that cause these patterns. Introduction: Coppicing woodlands is a method by which trees such as hazel and ash are cut back to almost ground level, leaving just the stumps or 'stools', from which many new shoots will grow from. The wood cut from these trees was once used for a wide variety of things, including thatching spars and firewood. As the trees were cut back, this allowed a lot more light to reach the woodland floor, allowing a greater diversity of both plant and animal life-forms to exist. After eight years, once the trees have many shoots which have grown back to replace those cut off, these are then cut off too between November and March, allowing even more shoots to grow in their place, and again allowing more light to the floor. This cycle continues, however, most coppices are now neglected and have consequently over-grown. Variables: Light- different amounts of light could cause a different variety of plants to grow in the separate coppices, as they will all photosynthesise at different rates. Also, a different light intensity could create different numbers of plants in the coppices, as well as causing them to be spread out over a wider area, creating more competition

  • Word count: 1603
  • Level: University Degree
  • Subject: Biological Sciences
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strategic development

INTRODUCTION Marks and Spencer (hereinafter called M&S) is one of UK's leading retailers of clothes, food, home products and financial services (Kippenberger 1997). M&S has a record of success and profitability since its establishment with well known reputation for its innovative, quality products and reasonable price which offers customers value for their money. M&S sales and services been declined in mid to late 1990s. The purpose of this report to identify the key drivers that made M&S falls in their performance. The external environment scanning is concerned with the forces and factors that impact upon M&S. However, analysing those forces and factors will assist M&S in identifying the change in the environment, is often referred to as the macro-environment, planning in how to cope with such a change, and being ahead of the competitors in the adaptation to the new environment and the response to the market demands. PESTEL framework and Porters Five Forces model are the techniques that author uses to identify and analyse the problems that M&S experienced in the mid to late 90's. Then the author carries out an internal analysis of the organisation's resources and competences. Resource audit, value chain and SWOT analysis are the techniques to examine the activity of the M&S in order to reveal what was the basis of their competitive advantage. Furthermore, the author

  • Word count: 4500
  • Level: University Degree
  • Subject: Biological Sciences
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An Investigation into Microclimate on a Sand Dune System

Geography Coursework: An Investigation into Microclimate on a Sand Dune System - First Draft Introduction Aim To provide detailed place study of a sand dune system on the Mediterranean coast. In particular to:- * Understand the physical morphology of sand dune systems * Consider the role of succession in the development of sand dune systems * Consider the impact of tourism on fragile ecosystems and consider how this can best be managed. We will be visiting a sand dune on the south coast of France near Montpellier; here will conduct our investigation and collect data to be used to complete our objectives. Objectives Profile To predict where ground temperature, soil temperature, air humidity, air temperature and wind speed will be higher and lower, and how to collect this data. Predictions for each Variable Ground Temp - I predict that the ground temp will be higher on the peaks and lower in the troughs this would be because the peaks would be more exposed to the sunlight whilst being to low to be affected by the wind. The troughs I expect to slightly overcast by the shadows of the peaks and marrum. Soil Temp - I predict that the soil temperature will gradually get cooler the further away from the sea the readings are taken. This would be because the further back you get the more vegetation and woodland you get which would shelter and therefore cool the soil.

  • Word count: 1883
  • Level: University Degree
  • Subject: Biological Sciences
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